Abstract :
[en] The Pregnancy-Associated glycoproteins (PAGs) constitute an asparatic proteinase family and are divided into 2 groups; bovine PAG-1 (boPAG-1) group and boPAG-2 group. PAGs have been detected in many domestic ruminant species and their biochemical characteristics were reported. However, information in wild ruminant, especially in deer species is scarce. The aim of this study is to investigate the characteristics of placental protein extracted in red deer (cervus elaphus); placental proteins which belong to each type of PAG group were identified in purification steps. Fresh frozen placenta (fetal cotyledon (FC): 2,247 g, maternal cotyledon (MC): 2,255 g respectively) was used as following purification step; protein extraction, acid precipitation (pH 4.5), Ammonium sulfate precipitation (SA0-40%, SA40-80%) and anion exchange chromatography (DEAE-cellulose 0M, 0,02M, 0,04M, 0,08M, 0,16M and 0,32M NaCl). In every step, Immunoreactivity against anti-PAG antisera was checked by Radioimmunoassay with using anti-PAG-1 antiserum (AS706) and anti-boPAG-2 antiserum (AS438). After Ammonium sulfate precipitation, much higher concentrations were gained in SA40-80% step (AS706: 5.35 mg/FCkg and 6.73 mg/MCkg, AS438: 24.79 mg/FCkg and 84.6 mg/MCkg) than SA0-40% step (AS706: 0.64 mg/FCkg and 0.79 mg/MCkg, AS438: 1.3 mg/FCkg and 9.34 mg/MCkg) in both part of cotyledon. After DEAE chromatography, the highest concentrations of protein against AS438 were gained in 0.08M NaCl step (5.49 mg/FCkg and 17.8 mg/MCkg) and concentrations of protein against AS706 were almost same in 0.08M NaCl (1.01 mg/FCkg and 1.35 mg/MCkg) and 0.16M NaCl (0.93 mg/FCkg and 1.34 mg/MCkg). In many ruminants such as cattle, sheep and goat, PAGs are contained largely in fetal cotyledon and most amounts of PAGs are belonging to PAG-1 group. On the other hand, in red deer, much larger amount of PAGs was obtained from maternal cotyledon. And stronger immunoreactivity with anti-boPAG-2 antisera was detected than with anti-PAG-1 antisera. This characteristic is similar to the results which were reported in pig and dromedary. Therefore, these results suggest that PAGs in red deer have different characteristics from other ruminant species.
